Genetic rearrangements have been suspected to play a crucial role in causing cells to become tumorigenic. This includes the rearrangements that lead to new gene orders within chromosomes as well as the integration of oncogenic viral DNA into the cell chromosome. The major emphasis of this research proposal is toward a kind of genetic rearrangement called gene translocation which is when a gene or group of genes with a defined site in one chromosome can reappear at new locations on the same or other chromosomes. The system for these studies is on a gene for kanamycin resistance in bacteria that has an inherent property of being able to translocate at relatively high frequency. The bacteriophage lambda chromosome is used as carrier for the kanamycin resistance genes for these studies. This work involves a genetic and biochemical analyses of lambda and its host Escherichia coli as is relevant to the translocation process. An effort is being made to isolate mutants in E. coli genes and in the translocatable kanamycin resistance genes that effect the translocation process. Experiments are also proposed to develop cell free conditions where the translocation reaction will occur.